Method for powering a liftgate with solar energy

ABSTRACT

A method for generating electricity from solar power to a liftgate, relying on a photovoltaic panels ( 1 ) circuit interruption device ( 3,9 ); charge controller ( 4 ); batteries ( 5 ); liftgate ( 7 ); electrical wires, and fuses. The photovoltaic panel(s) will generate electrical power that will provide sufficient power to run the liftgate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 12/795,009 filed Jun7, 2010, which is a continuation of U.S. patent application Ser. No. 12/426,927 filed on Apr. 20, 2009, the contents of which applications are herein incorporated by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to the field of solar electricity generated by photovoltaic panels and the application to run a liftgate.

BACKGROUND OF THE INVENTION

This method relates to the solar power used to charge batteries specifically designed and dedicated to the operation of a lift gate.

Examples of solar-power generators for vehicles are described in the following documents: U.S. Pat. No. 5,725,062, which was issued to Froneck on Mar. 10, 1998 described a vehicle top solar power generator, where the solar panel is mounted on the top of the vehicle.

U.S. Pat. No. 4,602,694, which was issued to Weldin on Jul. 29, 1986, was limited to a detailed combination of a motor, a generator, a traction wheel and other devices. U.S. Pat. No. 5,148,736 which was issued to Juang on Sep. 22, 1992, described an automatic solar-powered car ventilator.

U.S. Pat. No. 5,680,907, which was issued to Weihe on Oct. 28, 1997, described an auxiliary solar-power automobile drive system which would be an alternative source of power for the primary source of fossil fuel energy. This provided the logic but not a solution to provide enough solar power to a liftgate.

U.S. Pat. No. 6,380,481 which was issued to Muller on Apr. 30, 2002, involved solar panels which were used but they were retractable and the system was designed to run with the assistance of kinetic energy.

Our method involves a unit that is permanently affixed to the vehicle. It is designed to provide a specific service, which is an alternate power source for the operation of a liftgate otherwise require the costly operation of the main drive engine while the vehicle is parked or while it remains stationary for any significant period of time. Our method will greatly reduce the unnecessary idling of such vehicle or equipment, which will increase compliance with State and Federal Idling Laws. In a 1987 article, McCosh, D. “Racing with the Sun”, Popular Science Magazine, November 1987, McCosh noted that solar energy was a great source of electricity.

Back in 1987 McCosh was hoping for a technical breakthrough which would reduce the cost of solar panels, and now 22 years later we have the method to generate electricity for the purpose of running a liftgate for a fraction of the cost, as sought in 1987.

In his book, Tertzakian, P. “A Thousand Barrels a Second: The Coming Oil Break Point and the Challenges Facing an Energy Dependent World”, McGraw-Hill Professional, 2006, 8,23,79, Tertzakian explained the importance of getting away from the “oil only world” we live in and start to build a portfolio of energy sources. Solar power is mentioned in his book as an important part of such an energy portfolio. This method fits Tertzakian's description perfectly as we are not replacing the power source of the vehicle, but we are providing an additional power source that will be added to the overall power use and efficiency of the vehicle, specifically in the liftgate. If the liftgate is ran with some or all of his power consumption coming from solar energy the overall fuel use by the vehicle will drop, and therefore a saving will start to be realized immediately by the consumer.

Finding a replacement for oil fuels is the main purpose of several books and authors in the recent years. In his book Campbell, C. J. “Oil Crisis,” multi-science publishing, 2005, 303, also brought up the necessity of finding alternative energy sources.

SUMMARY OF THE INVENTION

In light of the publicly perceived need for solar energy for transportation vehicles and/or at minimum the supplementation of the power source for the vehicle, the object of our method is to provide a solar supplemental power source to the liftgate. This document will describe the construction of a device capable of providing a solar energy power source to operate a liftgate. This method is powered by solar power and is designed using readily available products. The solar output of this device is approximately 816 Watts, 33 Volts and 24.6 Amperes. The system can be configured for different levels of desired power, current and/or voltages, but our system is optimized for usage at this configuration. The batteries used for this project are approximately 12 Volts, 290 amperes per hour, but can be configured to meet the 24 Volts at 870 amperes per hour, desired application. Power from the solar power system and battery backup is regulated by means of a “charge controller.” This device provides optimal power usage from the panels while regulating the amount of charge going to the batteries and liftgate. The Direct Current (DC) disconnect in this system provides an extra layer of safety and facilitate efficient interconnection of the unit with tractor/trailer.

All of the energy generated by the solar panels is stored in batteries which have the following characteristics:

-   -   Completely sealed valve regulated;     -   Flame arresting pressure regulated safety sealing valves;     -   Operating pressure management and protection against atmospheric         contamination;     -   Computer-aided 99.994% pure heavy-duty lead calcium grid         designs; Tank formed plates, which guarantees evenly formed and         capacity matched plates;     -   Anchored plate groups, to guard against vibration;     -   Double insulating micro porous glass fiber separators;     -   Measured and immobilized electrolyte, for a wide range of         operating temperatures, and low self discharge rates     -   High impact reinforced strength copolymer polypropylene cases         with flat top designed covers that are rugged and vibration         resistant;     -   Thermally welded case to cover bonds that eliminate leakage;         Copper and stainless steel alloy terminals and hardware;     -   Multi-terminal options;     -   Terminal protectors;     -   Removable carry handles;     -   and     -   Classified as “NON-SPILLABLE BATTERY” Not restricted for Air         (IATA/ICAO) Provision 67, Surface (DOT-CFR-HMR49) or Water         (Classified as non-hazardous per IMDG amendment 27)         transportation, compatible with sensitive electronic equipment,         Quality Assurance processes with ISO (4400/992579), QS and TUV         Certification EMC tested, CE, ETTS Germany (G4M19906-9202-E-16),         Tellcordia and Bellcore compliant, UL recognized and approved         components (MH29050).

The method utilizes electrical connections with heavy duty cables with a zinc die-cast plug housing. Which is reinforced for durability, good recoil memory, chemical resistance and abrasion resistance. A temperature rating of −90° F. to 125° o F (−68° C. to 52° C.), unbreakable PERMAPLUGS™ featuring Dupont® patented material, which meets SAE J560. Large finger grips for coupling/uncoupling, even with gloves on. Extended plug interior for easy maintenance, protected with anti-corrosive non- conductive, dielectric lithium grease. All cable assemblies are rated for 12 volt systems. All electrical wires connect with the STA-DRY® Wire Insertion Socket, 7-Way #16-720D, with split brass pins along with Anti-Corrosive Dupont Super-Tuff Nylon® housing & lid and stainless steel hinge pin & spring, with inner cavity sealed to prevent contaminants from passing to the wire harness. Extended front barrels for additional cable support, slanted 5° for moisture drain, and elongated holes for mounting adaptability.

All electricity is generated by photovoltaic laminate solar panels. Each solar panel has the following characteristics: rated power (Pmax) 144 Watts, production tolerance ±5%;, by-pass Diodes connected across every solar cell to protect the solar cell from power loss in case of partial shading or damage of individual solar cells while other cells are exposed to full sunlight.

The adhesive to secure the unit to the vehicle's roof is an ethylene propylene copolymer adhesive-sealant, with microbial inhibitor, high temperature and low light performance. The adhesive is flexible and lightweight, weighting approximately one pound per square foot, compared to five pounds per square foot for standard adhesives. The unit is adhered directly to the roof without penetrations or perforations which is approved by state revenue departments for tax incentives and rebates.

The logical center for this method is a charge controller. The charge controller we selected has the following characteristics: PWM series battery charging (not shunt); 3-position battery select (gel, sealed or flooded); very accurate control and measurement jumper to eliminate telecom noise; parallel for up to 300 Amperes temperature compensation; tropicalization: conformal coating, stainless-steel fasteners & anodized aluminum heat sink, no switching or measurement in the grounded leg, 100% solid state, very low voltage drops, current compensated low voltage disconnect, leads for battery status and faults indication, capable of 25% overloads, remote battery voltage sense terminals. The charge controller has the following electronic protections: short-circuit for solar and load, overload for solar and load, reverse polarity, reverse current at night, high voltage disconnect, high temperature disconnect, lightning and transient surge protection, loads protected from voltage spikes, automatic recovery with all protections.

BRIEF DESCRIPTION OF THE DRAWINGS

The method for generating electricity from solar panels to run a liftgate is described by the appended claims in relation to the description of a preferred embodiment with reference to the following drawings which are described briefly as follows:

FIG. 1 is the electrical diagram of the method;

FIG. 2 is a partially cutaway top view.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference is made first to FIG. 1. Photovoltaic (PV) panels 1 that receive solar energy. The electricity generated by the PV panels 1 is transmitted via a wire 2, to a Circuit Interruption Device 3 (CID). If the CID circuit 3 is closed, the electricity generated by the PV panels 1 is transmitted via a wire 4 to a charge controller 5. The charge controller 5 is designed to direct the electrical current from the PV panels 1 to a primary load 7 in this embodiment a liftgate 7 via a wire 6. If the primary load 7 is not receiving the electricity generated by the PV panels 1 the charge controller 5 sends the electricity via a wire 8 to a second Circuit Interruption Device (CID) 9. If the CID circuit 9 is closed, the electricity sent by the charge controller 5 is transmitted via a wire 10, to the batteries 11. The batteries 11 store the electricity generated by the PV panels 1. When there is no electricity generated by the PV panels 1 the charge controller 5 allows the electricity stored in the batteries 11 to be transmitted via wire 10, then via CID 9 and wire 8, to the primary load 7. The charge controller 5 has the capability to be programmed to understand what is the circuit's current needs. This is based on the program set in the charger controller 5 memory. The unit will be able to make logical decisions (based on the charger programmed data). If the load 7 needs power, the charge controller 5 sends electrical power to the load. If the batteries 11 are low in charge, the charge controller 5 sends power to the batteries 11.

As shown in FIG. 2, the batteries 11 will be assembled and installed under the (vehicle's) truck trailer carriage The wire 2 makes an approximately 90° bend and comes down to the side of the trailer where it is going to be connected with the CID 3, which is assembled and installed on the front of the trailer 12. From the CID 3, the wire 4 brings the electricity generated by the PV panels 1 to the charge controller 5 which is also mounted to the front of the trailer 12. The CID 9 is also assembled on the front of the trailer 12. Safety is of great concern of this invention. As such, both CID 3 and 9 are in installed in this manner and method to provide an extra layer of safety and to facilitate an efficient interconnection of method for generating electricity from solar panels with its liftgate. The vehicle operator can safely reach the controls for the CID 3 or the CID 9 which are placed on the side of the trailer 12, and disconnect the PV panels 1 for any necessary service, without risk of getting an electric shock, since the PV panels 1 are always generating electricity when exposed to light. The same principle is applied to the CID 9 if service needs to be performed to the batteries 11, the operator can safely close the switch in the CID 9 and work on the batteries without the risk of an electrical shock.

This method was conceived to work as two separate systems with one point of interconnection being the charge controller 5. The first system will be comprised of the PV panels 1, the CID 3 and the charge controller 5. The second system will be comprised by the batteries 11, the CID 9 and the charge controller 5.

After our method is completed and attached to the trailer 12, our method will generate enough power to provide the liftgate 14. Although the foregoing invention has being described in some detail by way of illustration and example, for purposes of clarity and understanding, it is obvious that certain changes and modifications may be practiced within the scope of the appended claims.

As described in the first embodiment the load 7 can be an electrical equipment that is not a liftgate. The application of the method will be the same, and the technical specifications will remain the same, but the electrical equipment or load will of a different kind, the system can be reconfigured to generate less electricity if necessary, and based on today's technology. Also if future technologies arise that would require more electricity this machine's capabilities can be extended by adding more solar panels 1 and more batteries 11. 

That which is claimed is:
 1. A method of operating a trailer lift gate with a solar power system, the method comprising: arranging a charge controller between at least one trailer-mounted photovoltaic solar panel, at least one vehicle-mounted battery and at least one trailer lift gate; automatically detecting solar panel power generation, trailer lift gate electrical power consumption, and battery charge with the charge controller; and selectively routing power between the at least one solar panel, the at least one trailer lift gate, and the at least one battery using the charge controller, dependent on the detected power generation, power consumption and battery charge.
 2. The method of claim 1, further comprising isolating the at least one solar panel from the charge controller, the at least one vehicle-mounted battery and the at least one trailer lift gate using a DC disconnect.
 3. The method of claim 1, further comprising isolating the at least one battery from the charge controller, the at least one vehicle-mounted solar panel and the at least one trailer lift gate using a DC disconnect.
 4. The method of claim 1, further comprising the isolating the charge controller and the at least one trailer lift gate from the at least one vehicle-mounted solar panel and the at least one battery using respective DC disconnects. 